A liquid crystal display (LCD) is a planar and ultrathin display apparatus, which is constituted by a number of colored or black and white pixels that are placed in front of a light source or a reflection plate. The LCD has very low power consumption, and is advantageous in its high image quality, small size and light weight, thus is very popular and becomes a mainstream among displaying products. The LCD has been widely applied to various electronic products, such as a computer having a display screen, a mobile phone or a digital photo frame, while a wide view angle technology is one of develop priorities of the current LCD. However, when the viewing from the side or squinting, if a view angle is too large, a color shift phenomenon might occur to the wide view angle LCD.
To solve the color shift problem of the wide view angle display, a technology called 2D1G is adopted in industry. The 2D1G technology refers to dividing each pixel unit in the liquid crystal panel into a main pixel and a sub pixel having different areas, and the main pixel and sub pixel in the same pixel unit are connected to different data lines and the same gate line. Different display brightness and squint view brightness can be generated by inputting different data signals (i.e. different grayscale values) into the main pixel and the sub pixel, so as to reduce the color shift occurred when viewing from side and squinting. Regarding a grayscale value of a pixel unit, there still remains a problem as for how to set the grayscale values of the main pixel and the sub pixel respectively, so that a combination of the grayscale values of the main pixel and the sub pixel may achieve a better display effect when reducing the color shift problem.